1. Field of the Invention
The present invention relates, generally, to air freshener canisters having a central supply vessel containing an aromatic liquid that is surrounded by an evaporation chamber enclosing a generally cylindrical wick that is wetted by liquid escaping from the supply vessel. More particularly, the present invention relates to a spill-resistant air freshener canister that has no unabsorbed standing aromatic liquid outside the vessel, with all aromatic liquid that has seeped from the supply vessel being absorbed by the wick.
2. Description of the Prior Art
Aromatic fluid delivery devices, such as fragrance dispensers, have been known in the art for many decades. One example of a dispenser for volatile fluid is disclosed in three related U.S. Pat. Nos. 5,533,705; 5,816,846 and 6,105,916. The device provides a drive selectively using a large or small motor providing an air stream for generating vapor from a wick, ceramic wafers, or discs containing vaporizable deodorant. Socket assemblies provide a socket for a motor of larger dimensions and a socket for a motor of smaller dimensions. A frame for a cabinet composed of a separate back plate, a top member and a bottom member of a resilient plastic so that the top member and bottom member are snap-locked to the back plate and secured further by projections from the top and bottom members in slots in the back plate. The bottom member is a liquid tight tray capable of processing deodorants contained in wick-equipped bottles and cans, porous impregnated ceramic discs, and porous impregnated fiber wafers. There is a bottle holder snap-locked to the underside of the top member. A battery-blower assembly is snap-locked to the back plate. The battery poles are joined to the wires from the blower-motor by clips using solderless connections.
More recently as disclosed in U.S. Pat. No. 6,957,779 is a framed fluid delivery device that is made up of a fluid-delivery cartridge for the timed-release delivery of a fluid. The fluid delivery cartridge retained by a frame assembly uses a base portion for the delivery of fluid released from a cartridge. The base secures the fluid delivery cartridge within the frame assembly proximate the end when fluid is released. The fluid-delivery cartridge has a bottom, a top, and sides, and a dispersion pad positioned proximate the bottom of the fluid-delivery cartridge that at least partially surrounds the sides of the fluid-delivery cartridge. A generator that generates gas is used for powered discharge of volatile liquid from the storage cell that is part of the fluid delivery cartridge. While conventional dispensers have been readily utilized in numerous commercial markets, they have not been configured to automatically dispense a fluid at predetermined intervals. In particular, many conventional dispensers are manually or electromechanically actuated by depressing, for example, a cap, a button, or a trigger mechanism. Such manually, or electromechanically actuated dispensers are cumbersome and expensive inasmuch as they have many costly components.
A more recent trend has seen the proliferation of fragrance canisters which have a central fluid supply vessel surrounded by an evaporation chamber enclosing a wick. U.S. Pat. No. 6,283,461 to Ashok Joshi, et al. discloses a fluid delivery device including a container for holding a predetermined quantity of fluid, a gas generator for generating gas within the container, and a dispenser for cyclically dispensing fluid at predetermined intervals out of the container without cyclical actuation by a user. Although the Joshi, et al. device represents an improvement in the art, in that the cost of fragrance dispensers is substantially reduced, the device is still unnecessarily complex and relatively costly.
U.S. Pat. No. 8,005,350 to Arnold H. Zlotnik, et al. discloses an arom atic odor neutralizer that includes a vaporization chamber containing a wick with an end part immersed in fluid in a storage cup that is gravity fed from an airtight vessel by the use of air pathways exposed when the liquid level in the cup is reduced. The vaporization chamber is located in a dispenser housing with an internal passage between end walls and communicating with vents in the sides for aerodynamic airflow to efficiently absorb vapors from a vaporizer chamber. Once activated by puncturing a lower portion of the vessel, the Zlotnick, et al. device soon reaches an equilibrium condition characterized by the presence of standing aromatic fluid in the storage cup. This standing fluid is subject to spillage if the air canister is not handled with care.